1545. The improved separation method of coherent sources with two measurement surfaces based on statistically optimized near‑field acoustical holography

Jin Mao1, Zhongming Xu2, Zhifei Zhang3, Yansong He4, Shu Li5

State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing, 400030, China

1Corresponding author

E-mail: 1mao-jin@cqu.edu.cn, 2xuzm@cqu.edu.cn, 3cquzzf@cqu.edu.cn, 4hys68@cqu.edu.cn, 520120702141@cqu.edu.cn

(Received 16 July 2014; received in revised form 13 September 2014; accepted 5 October 2014)

Abstract. A technique for separating coherent sources measured by two parallel arrays is proposed. The two measurement surfaces located in the opposite directions of the coherent sources. Similar to separate the aim source from background noise, this method can separate the single source from coherent sources, which makes the sound field information of single source in complex environment more accurate. Such improved separation method based on statistically optimized near-field acoustical holography, according to the sound pressure relationship between measurement surfaces and reconstruction surfaces to separate the sources, reduces the measurement data and obtains higher precision of reconstruction. The present paper uses the improved separation method to obtain the single source results from numerical simulations, gives the relative reconstruction errors with frequency from 100 Hz to 1400 Hz, and practical measurement.

Keywords: statistically optimized, sound field separation, acoustical holography.

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Cite this article

Mao Jin, Xu Zhongming, Zhang Zhifei, He Yansong, Li Shu The improved separation method of coherent sources with two measurement surfaces based on statistically optimized near‑field acoustical holography. Journal of Vibroengineering, Vol. 17, Issue 2, 2015, p. 674‑681.

 

JVE International Ltd. Journal of Vibroengineering. Mar 2015, Volume 17, Issue 2. ISSN 1392-8716